How long can you hold your breath? I’m trying it right now. The first 30 seconds are easy. I’m ready to give up at 45 seconds but I push on through and it seems to get easier for a while. But, as the second hand ticks past a minute, I know I’m on borrowed time. My heart is pounding. I let out a tiny breath and this helps. Eventually, I give in, expelling the spent air in my lungs and taking a huge gasp. (And continue to gasp for a few more breaths, prompting my husband to ask what on earth I’m doing.) I manage one minute and 12 seconds. I’m quite impressed with myself. Breath-holding ability becomes extremely important in some sports, particularly freediving. In 2006, I was filming a programme about the anatomy and physiology of the lungs for a BBC series called, slightly oddly, Don’t Die Young. I was lucky enough to meet Sam Amps, who was captain of the UK freedive team. At a pool in Bristol, she taught me some simple exercises to help me hold my breath for longer while swimming underwater. By the end of the session, I think I’d managed a prodigious 90 seconds of breath-holding, enough to let me swim a width. Sam swam three widths with ease. She could hold her breath for five minutes, while swimming. Five! I asked how she did it: very slow breathing for several minutes prior to each dive, then a big, deep breath before diving in. She also said training